Answer:
The molarity of the solution is 1.1 
Explanation:
Molarity is a measure of the concentration of that substance that is defined as the number of moles of solute divided by the volume of the solution.
The molarity of a solution is calculated by dividing the moles of the solute by the volume of the solution:

Molarity is expressed in units 
In this case
- number of moles of solute= 0.564 moles
- volume= 0.510 L
Replacing:

Solving:
molarity= 1.1 
<u><em>The molarity of the solution is 1.1 </em></u>
<u><em></em></u>
Cl-35, as the atomic mass of Chlorine (35.45) is closer to the number 35 than to the number 37. A higher abundance of CL-35 isotope would have caused the atomic number (which is an average of the values of all isotopes of a substances taking relative abundance into consideration) to decrease from 36, which would appear to be the average.